UNC1999 is an orally active inhibitor of EZH2 (IC50=2nM) and EZH1 (IC50=45nM)[1-2]. UNC1999 can be used to investigate the mechanisms of EZH2 and EZH1 in gene expression regulation, cancer development, and stem cell maintenance[3-4].
In vitro, treatment of human colorectal cancer cells (HCT116, LoVo, HCT-15, DLD-1) with UNC1999 (2.5–5μM) for 24–72 hours induces autophagy by upregulating LC3B gene expression transcriptionally, activates endoplasmic reticulum (ER) stress and the PERK/eIF2α pathway of the unfolded protein response (UPR), ultimately promoting tumor cell death[5]. UNC1999 (0.1–100μM) treatment of human bladder cancer cell lines E-J and 5637 for 24–120 hours, UNC1999 significantly inhibits cell proliferation and migration while inducing apoptosis by suppressing EZH2 activity and blocking the JAK2/STAT3 signaling pathway[6].
In vivo, intraperitoneal injection of UNC1999 (15–25mg/kg) twice weekly for 3 weeks in NOG mice bearing MM.1S human multiple myeloma xenografts significantly inhibits tumor growth and prolongs survival[7]. Intraperitoneal injection of UNC1999 (25mg/kg) twice weekly for 4 weeks in BALB/c nude mice inoculated with Y79 human retinoblastoma cells significantly suppresses the growth of subcutaneous xenograft tumors[8].
References:
[1] Zhou C, He A, Kang Q, et al. Development of a UPLC-MS/MS method for determination of a dual EZH1/2 inhibitor UNC1999 in rat plasma. Bioanalysis. 2022 Jan;14(2):67-74.
[2] Xu B, On DM, Ma A, et al. Selective inhibition of EZH2 and EZH1 enzymatic activity by a small molecule suppresses MLL-rearranged leukemia. Blood. 2015 Jan 8;125(2):346-57.
[3] Shinno Y, Takenobu H, Sugino RP, et al. Polycomb EZH1 regulates cell cycle/5-fluorouracil sensitivity of neuroblastoma cells in concert with MYCN. Cancer Sci. 2022 Dec;113(12):4193-4206.
[4] Zhang Q, Deng X, Tang X, et al. MicroRNA-20a Suppresses Tumor Proliferation and Metastasis in Hepatocellular Carcinoma by Directly Targeting EZH1. Front Oncol. 2021 Dec 16;11:737986.
[5] Hsieh YY, Lo HL, Yang PM. EZH2 inhibitors transcriptionally upregulate cytotoxic autophagy and cytoprotective unfolded protein response in human colorectal cancer cells. Am J Cancer Res. 2016 Aug 1;6(8):1661-80.
[6] Chen Z, Du Y, Liu X, et al. EZH2 inhibition suppresses bladder cancer cell growth and metastasis via the JAK2/STAT3 signaling pathway. Oncol Lett. 2019 Jul;18(1):907-915.
[7] Rizq O, Mimura N, Oshima M, et al. Dual Inhibition of EZH2 and EZH1 Sensitizes PRC2-Dependent Tumors to Proteasome Inhibition. Clin Cancer Res. 2017 Aug 15;23(16):4817-4830. doi: 10.1158/1078-0432.CCR-16-2735.
[8] Zhao Y, Cheng Y, Qu Y. The role of EZH2 as a potential therapeutic target in retinoblastoma. Exp Eye Res. 2023 Feb;227:109389.
UNC1999是一种口服活性的EZH2(IC50=2nM)和EZH1(IC50=45nM)抑制剂[1-2]。UNC1999可用于研究EZH2和EZH1在基因表达调控、癌症发生发展以及干细胞维持中的作用机制[3-4]。
在体外,UNC1999(2.5–5μM)处理人结直肠癌细胞(HCT116, LoVo, HCT-15, DLD-1)24–72小时,UNC1999通过转录上调LC3B基因表达诱导细胞自噬,并激活内质网应激(ER stress)及未折叠蛋白反应(UPR)的PERK/eIF2α通路,最终促进肿瘤细胞死亡[5]。UNC1999(0.1–100μM)处理人膀胱癌细胞系E-J和5637 24–120小时,UNC1999通过抑制EZH2活性并阻断JAK2/STAT3信号通路,显著抑制细胞增殖和迁移、诱导细胞凋亡[6]。
在体内,UNC1999(15–25mg/kg)每周2次腹腔注射,用于处理携带MM.1S人多发性骨髓瘤异种移植瘤的NOG小鼠,持续3周,显著抑制了肿瘤生长并延长了小鼠生存期[7]。UNC1999(25mg/kg)每周两次腹腔注射,用于处理接种了Y79人视网膜母细胞瘤细胞的BALB/c裸鼠,持续4周,UNC1999显著抑制了皮下移植瘤的生长[8]。
















